<!DOCTYPE html>
<style>
#div {
  box-shadow: -50px 0 red;
  position: absolute;
  top: 100px;
  left: 100px;
  width: 100px;
  height: 100px;
  writing-mode: vertical-rl;
  background-color: blue;
}
</style>
Tests paint invalidation of a verticle-rl div with overflow. Passes if no under-invalidation reported and shows no red.
<div id="div"></div>
<script src="../resources/text-based-repaint.js"></script>
<script>
function repaintTest() {
  div.style.boxShadow = '-50px 0 green';
}
onload = runRepaintAndPixelTest;
</script>
